Support adopting an existing EGLContext in eglfs and xcb

Add also a manual test application. For GLX there is an autotest since
that is likely to be run on one of the CIs. For EGL and especially
eglfs this is likely not the case so a manual test is better.

Task-number: QTBUG-37552
Change-Id: Ib09db5d909befb68d16f69abd401a56abe55f28a
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/platformsupport/eglconvenience/qeglplatformintegration.cpp b/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
index 3de0642c93..560ff79ef8 100644
--- a/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
+++ b/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
@@ -158,9 +158,14 @@ QPlatformOpenGLContext *QEGLPlatformIntegration::createPlatformOpenGLContext(QOp
     // If there is a "root" window into which raster and QOpenGLWidget content is
     // composited, all other contexts must share with its context.
     QOpenGLContext *compositingContext = screen ? screen->compositingContext() : 0;
-    return createContext(context->format(),
-                         compositingContext ? compositingContext->handle() : context->shareHandle(),
-                         display());
+    QPlatformOpenGLContext *share = compositingContext ? compositingContext->handle() : context->shareHandle();
+    QVariant nativeHandle = context->nativeHandle();
+    QPlatformOpenGLContext *platformContext = createContext(context->format(),
+                                                            share,
+                                                            display(),
+                                                            &nativeHandle);
+    context->setNativeHandle(nativeHandle);
+    return platformContext;
 }
 
 QPlatformOffscreenSurface *QEGLPlatformIntegration::createPlatformOffscreenSurface(QOffscreenSurface *surface) const